<?php
namespace Chazz\Log;

class Log
{
    private $handler = null;
    private $level = 15;
    private static $instance = null;
    private function __construct() {}
    private function __clone() {}

    public static function Init($handler = null, $level = 15)
    {
        if (!self::$instance instanceof self) {
            self::$instance = new self();
            self::$instance->__setHandle($handler);
            self::$instance->__setLevel($level);
        }
        return self::$instance;
    }


    private function __setHandle($handler)
    {
        $this->handler = $handler;
    }

    private function __setLevel($level)
    {
        $this->level = $level;
    }

    public static function DEBUG(...$msg)
    {
        self::$instance->write(1, $msg);
    }

    public static function WARN(...$msg)
    {
        self::$instance->write(4, $msg);
    }

    public static function ERROR(...$msg)
    {
        $stack = "[";
        $debugInfo = (array)debug_backtrace();
        foreach ($debugInfo as $val) {
            if (array_key_exists("file", $val)) {
                $stack .= ",file:" . $val["file"];
            }
            if (array_key_exists("line", $val)) {
                $stack .= ",line:" . $val["line"];
            }
            if (array_key_exists("function", $val)) {
                $stack .= ",function:" . $val["function"];
            }
        }
        $stack .= "]";
        self::$instance->write(8, $stack . $msg);
    }

    public static function INFO(...$msg)
    {
        self::$instance->write(2, $msg);
    }

    private function getLevelStr($level)
    {
        switch ($level) {
            case 1:
                return 'debug';
                break;
            case 2:
                return 'info';
                break;
            case 4:
                return 'warn';
                break;
            case 8:
                return 'error';
                break;
            default:
        }
    }

    protected function write($level, ...$msg)
    {
        if(is_array($msg)){
            $msg = isset($msg[0]) ? $msg[0] : $msg;
            $msg = implode(',', $msg);
        }
        if (($level & $this->level) == $level) {
            $msg = '[' . date('Y-m-d H:i:s') . '][' . $this->getLevelStr($level) . '] ' . " \t " . $msg . "\n";
            $this->handler->write($msg);
        }
    }
}
